Iterative Implementations for Linear Multiuser Detectors
نویسندگان
چکیده
We consider the convergence properties of several iterative implementations of linear multiuser receivers, under the assumption of long random spreading sequences. We nd that parallel interference cancellation diverges for systems loads of greater than 17%. Using known results from the theory of iterative solutions for linear systems, we derive optimal or near optimal relaxation parameters for parallel ( rst and second order stationary, Chebyshev) and serial cancellation (successive relaxation) methods. An analytic comparison of the asymptotic convergence factor for the various methods is given. Simulations are used to verify results for nite size systems.
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